The different types of Covid-19 tests

3 Types of COVID-19 Tests, and Which One Is the Most Accurate

https://www.health.com/condition/infectious-diseases/coronavirus/covid-19-test-types 

  Health authorities worldwide use either RT-PCR or RTK-Ag to test the virus

 There are two known popular Covid-19 tests available and used by the health authorities worldwide to detect the virus.

The two tests – reverse transcription polymerase chain reaction (RT-PCR) and antigen rapid test kit (RTK-Ag) – require nasal or throat swab samples.

RT-PCR is considered the gold standard in diagnosing the Covid-19 virus.

It can detect if an individual has an active Covid-19 infection and the test has typically high sensitivity rates, though this also means the sample has to be carefully prepared to avoid contamination.<

RT-PCR is a molecular test that is able to detect minute quantities of Covid-19 virus’s ribonucleic acid (RNA) in the nasal or throat swab sample taken from an individual.

Chemicals are used on the swab to remove other substances and extract only the RNA in the sample.

The RNA is converted to DNA through the “reverse transcription” process, and extra short fragments of DNA are added by scientists to build DNA strands and to add marker labels to them to detect the virus.

The mixture is placed in a machine that creates copies of the viral DNA, during which the marker labels release a fluorescent dye that is measured by a computer.

Depending on the lab and logistics, results can be obtained in two hours, or up to several days if the sample needs to be shipped across distances.

The RTK-Ag test, on the other hand, is faster than the RT-PCR test, as it can generate results within 15 to 30 minutes.

As such, RTK-Ag has the advantage of detecting Covid-19 outbreaks quickly and in large quantities, but its accuracy is lower than the RT-PCR test and it may produce false-negative results (leading to a false sense of security).

The Health Ministry uses the RTK-Ag as an alternative to the RT-PCR in certain situations, in order to obtain test results within a shorter time in circumstances where molecular testing is not available.

Antigen tests work by detecting specific proteins on the surface of the virus, as opposed to the RT-PCR test which detects the virus’s genetic material.

Yet another Covid-19 test is the antibody test, which unlike the RT-PCR and RTK-Ag tests, is detected through a blood sample. Samples are obtained via pricking the finger or drawing of blood, and results can be obtained within a few days.

However, the antibody test is not suitable to be used to detect active Covid-19 infections as it can only show that a person has been (or never been) infected by the virus in the past.

The test picks up on antibodies, which are proteins created by a person’s immune system after they have been infected or vaccinated.

According to the US Centers for Disease Control and Prevention, it will take one to three weeks after infection for a person’s body to produce antibodies.

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Nation 22 Jan 2021

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Ways to fight raging Covid-19 fire

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Housekeeping Covid-19 away: ways to disinfect your home

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Ways to fight raging Covid-19 fire

 

MANY individuals and groups have shared suggestions of how to manage the Covid-19 pandemic. Allow me to summarise five key measures we critically need to take to manage the crisis.

Test extensively:

Ramping up our PCR (reverse transcription polymerase chain reaction) tests to 100,000 a day is insufficient. PCR tests are labour intensive and results are usually delayed. If it takes three to five days to get a result, this limits the value of the testing.

We need hundreds of thousands of RTK-Ag (antigen rapid test kit) tests on the ground. With a one- hour result time they offer rapid response and action when positive.

Even if they are only 75% sensitive, it significantly mutes the pandemic. Equivocal results can be sent for PCR testing. We should keep PCR tests for patients requiring admission and testing of high risk symptomatic persons (over 60 years with major comorbidities).

Restore contact tracing:

Contact tracing activities have been swamped by the huge numbers and have currently failed. We must learn from other nations.

Rapidly employ the more than 10,000 retrenched non-medical professionals, train and use them to re-establish contact tracing in all states. This will also free healthcare staff to do more vital tasks.

We must dramatically improve our handphone applications to allow for seamless contact tracing and notification of the public.

Support Health Ministry staff: 

Our Health Ministry staff are long past burnout. The burden of excessive work, long hours wearing PPE (personal protective equipment), fears of contracting Covid-19 and lack of adequate emotional support have wrought havoc on a healthcare system that was always fragile and inadequate.

We must immediately offer permanent jobs to all Health Ministry staff on contract, as well as hire all available doctors, pharmacists and nurses waiting for jobs. Also consider graduating all final year doctors, pharmacists and nurses, using their continued formative assessments and prior examination results as a proxy indicator of performance.

Improve home quarantine: 

Home quarantine is useful for Covid-19 individuals who are well and healthy. However, maintaining home quarantine for large numbers is a challenge. There are numerous reports of those who are supposed to be under home quarantine, either because they are positive or have been in close contact with a confirmed case, travelling outside their home to get food or visit a doctor.

In addition, many people are at a loss about what to do at home and are waiting for days for Health Ministry personnel to contact them. There must be a mechanism to improve current home quarantine conditions.

We should hire and train retrenched non-medical professionals and use them to monitor and support these individuals.

It may be important for the Health Ministry to offer hospitalised quarantine for those over 60 years of age with major comorbidities, as they are at high risk for death.

Widen pick up services:

 Individuals who are found to be Covd-19 positive and require hospitalisation should not have to wait. We hear many anecdotal reports of such persons waiting for days to be admitted.

We recognise that the Health Ministry’s ambulance services are overwhelmed. We need to urgently widen the pick-up services. We can train and use private ambulance services, especially for those who are really ill.

For those who are mildly ill and require hospitalisation, we could work with established transport services (taxis, Grab, etc) to provide a dedicated pick up service with good PPE and protection for the drivers.

When there is a huge fire raging in a large region, using hand-held fire extinguishers will not work. We cannot continue with the same initiatives we have practised thus far to control the vast local outbreak.

Using imaginative, out-of-the box strategies are necessary. No one person or organisation has all the solutions or answers. Listening to diverse views is critical.

DATUK DR AMAR-SINGH HSS , Senior Consultant Paediatrician

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Housekeeping Covid-19 away: ways to disinfect your home

  Ministry details cleaning solutions for patients self-isolating at home Clean those door knobs, tap faucets or other frequently touche...

 

The different types of Covid-19 tests

 

Housekeeping Covid-19 away: ways to disinfect your home

 

Ministry details cleaning solutions for patients self-isolating at home

Clean those door knobs, tap faucets or other frequently touched surfaces.

Now that Covid-19 patients with mild or no symptoms at all are required to self-isolate at home instead of going to a quarantine centre, the Health Ministry has provided guidelines on sanitising your home if you are living with an infected person.

According to the ministry, the bathroom used by the patient should be disinfected at least once a day.

To prepare for the disinfectant solution, use five tablespoons of 5% sodium hypochlorite with 3.8 litres of water or four teaspoons of 5% sodium hypochlorite with 0.95 litres of water.

“The personal protective equipment needed are face mask, face shield, plastic apron and gloves.

“Surfaces can be cleaned with a normal detergent first, rinse and then clean using the disinfectant solution containing 0.1% sodium hypochlorite, ” it noted, adding that the person sanitising should wash their hands before and after the cleaning process.

Also, the ministry said that those who were living with a Covid-19 patient at home should wear a mask and disposable gloves when handling the patient’s clothes.

“Dirty clothes and linen should be stored in a sealed plastic or closed storage until it is ready to be washed.

“The clothes should also be separated from others.

“Don’t shake the laundry as the virus can be transmitted through the air, ” it said.

Health experts said the public should sanitise and disinfect shared spaces within their own house and workspace and especially if there was a Covid-19 case in the area.

Universiti Putra Malaysia medical epidemiologist Assoc Prof Dr Malina Osman said one of the basic principles for sanitisation was whether there was a risk of virus exposure.

“It depends on whether there is presence of possible infection in the area or not, ” she said.

Dr Malina said if there was a positive case at the workplace, sanitisation needed to be done at the person’s work desk and common areas including lift, railing, door knobs, toilet and other identified areas.

“There is no need to have a blanket rule to sanitise the whole building, the road to the office or the drainage system, ” she added.

Public health assistant Muhamad Shahir Mohd Razali said it was safe to use disinfectants to clean surfaces that were regularly touched such as table tops and door knobs.

“This can also be done at the workplace where sanitisation can be done once every two weeks.

“And for surfaces that are regularly touched, they can do it twice a day.

“This will help reduce the risk of transmitting diseases and viruses, ” he added.

Shahir said his team often conducted sanitisation at places where a Covid-19 patient had been to such as quarantine centres, offices, crematoriums or cemeteries.

“We sanitise the areas with a chemical solution which is sodium hypochlorite and water mixed according to the required measurement.

“The areas that we sanitise are the toilet, kitchen, bedroom and common areas, ” he said, noting that the PPE worn during disinfection would later be discarded in a bio-hazard plastic bag sealed and sprayed with detergent.

Malaysian Medical Association president Prof Datuk Dr Subramaniam Muniandy said disposable gloves or gloves dedicated for sanitising surfaces should be worn when sanitising.

“The home should also be sufficiently ventilated when sanitising to protect against inhaling harmful chemical vapours from the disinfectant.

“Surfaces should be disinfected after they are cleaned with soap and water, ” he said, noting that disposable gloves or rubber gloves should be worn and discarded properly.

Dr Subramaniam said mobile phones should also be wiped clean and disinfected everyday as it was the most used device often placed on various surfaces.

He said frequently touched surfaces such as door handles, switches, table tops and chairs should be cleaned at least twice a day.

“Staff should get into the habit of washing hands frequently with soap and water or hand sanitiser.

“In smaller companies, staff should clean and disinfect their own workstation, ” he said, adding that face masks should be worn in the office to protect others and surfaces from respiratory droplets.

Dr Malina emphasised that the basic measure in preventing Covid-19 infection was to take care of personal hygiene.

“Any person who has to be at the office, regardless of their Covid-19 status, as it is often unknown, should always avoid touching unnecessary areas, always wash their hands when touching various surfaces and should never allow their nasal droplets or saliva to contaminate the office or public areas.

“If there is a possible contamination, it should be cleaned as soon as possible, ” she added.

Dr Malina said the current measures to prevent the spread of Covid-19 like working from home, reducing the number of employees to 30% and stricter SOP were adequate.

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